The capsizing or taking on water of relatively small boats continues to be a leading cause of death by drowning. Various life saving devices have been tried such as buoyant articles circular life preservers, and life vests but these have only been partially successful due to the fact that they have not provided the user with any relatively stable means of remaining afloat with his head above water nor of keeping the user with the boat.
When a relatively small boat is capsized or takes on appreciable water, its reduced buoyancy may h=such that if the occupants remain in or on the boat they and the boat will sink.
However, if the occupants get into the water its buoyant effect reduces their net weight so that even the reduced buoyancy of the boat may be adequate to keep them from drowning.
Further, in making a search for survivors of a boating accident it is usually much easier to locate the boat than it is to locate individual survivors. A person in the water, however, may not be able to hold on to a capsized or submerged boat, particularly over a length of time, so that he is likely to become separated from the boat.